Although knowledge is not the same as that of intelligence the fact remains that historical study is one way out of very many to expand intelligence. A study of the eonic effect takes this to the ultimate. Let me note that I exempt myself from the judgement since I had many years to cheat: my level of intelligence is above average (ca. 115, I guess, with verbal potentials, I can write a bad sonnet in fifteen minutes, a tad above the limerick), but not einsteinian.
The useful thing here is that everyone flunks the test, to start. So there is no nonsense about being smarter than anyone else: everyone starts off equally. Remarkably professional historians being highly specialized have proven blind to the eonic effect which is an exercise in pattern recognition stretching over the whole field of world history, but especially the last five thousand years, and over all regions equally distributed. Note the latter point, All regions equally distributed
The test, which takes one to four years is to read a thousand books on history and to find a non-random pattern in that data set (which you can extend to include the paleolithic and deep time, as history turns into evolution, so to speak, in fact the two are janus-faced ). You may cheat and use the eonic data in print such as it is and you are free to dissent from that interpretation and/or refute the claims: but you would do well to be wary of claiming that world history shows pure randomness): you can propose your own interpretation, wary that the eonic effect will likely falsify your own claims.

Note: one of those books may be World History and the Eonic Effect, can you cheat and just read that book? By all means, but unless you read the whole spectrum of books you may not know what your are reading…It is possible to complete the test in a few months. But everyone will call you crazy and the book bunk, so unless you read the books you will not win any arguments with the brainwashers trying to claim your mind.

On the way you must resolve a lot of difficulties: the nature of dynamical systems versus historical systems. The question, what is evolution? The key issues of philosophy form Plato to Kant, and their relationship to the overall exercise. The nature of religion in general and religions in particular: the case of christianity, versus buddhism, etc… But you don’t have to solve all those issues: you can up to a point simply describe them.
This impinges on the issue of nature/supernature, and the nature of secularism…the list goes on and on…There a dozens of such riddles on the way: you can put many on ‘hold’ and proceed without fully resolving them. But the issue of christian salvation (if any) and/or buddhist enlightenment, or the true tao enter inexorably. Delusions, myths? These will likely defeat you so you can adopt descriptive summaries. In addition the histories of science and technology enter along with those of the nature of economics. Do you need newtonian physics and/or quantum mechanics here? probably not, but a few sneak peaks at these subjects is in order.

I have made my point: detecting a pattern in world history is not a trivial task. One might claim that knowledge accumulation is not intelligence but the two blend into each other and as you attempt this your de facto intelligence will inexorably start to increase. etc…

Let me say at once that this exercise is not suitable in general and better ways to exercise the mind might be in order. Whatever the case, it is clear that there are dozens of similar projects to develop reasoning and intelligence, even as they impinge on unknowns, and unsolved riddles. This particular case extends beyond standard science, and religious faith, and is helped greatly by Kantian warnings about metaphysics…This is open to any level of intelligence with a guarantee it will be a brain stretcher…The issue of history is useful because it is open to any level as a staring point. The whole question could be done with a thousand history comic books, but with footnotes…
It might be claimed that old people with a whole life of study versus beginners with little knowledge are not comparable. Very true, but this is not a standard IQ test with a score at the end. There is no score, and the criticism that intelligence and knowledge are distinct is true, but not really the point. Since your intelligence will undergo change as your take the test, the idea of a score is meaningless.
It is in fact a process almost guaranteed to avail of neuroplasticity.

Find something similar in your given case, etc…
The point is that homo sapiens has barely scratched the surface of his ultimate potential. Such complex pattern recognition exercises must be abundant and deserve a future. Physics offers many things like this, but history is better because it is open to all levels as a starting point.

The nature of historical knowledge is highly controlled by ideological entities of all kinds, religious, academic, political, etc…They will move at once to denounce the data on the eonic effect. Offer them a simple reponse: have you read those thousand books?